A seat reclining device for a vehicle disclosed in, for example, Japanese Laid-Open Patent Publication No. 2006-271581 has been proposed. The seat reclining device includes a first cable, which is coupled to a memory operation lever, a lock mechanism, a lever member, which is coaxial with the lock mechanism, a second cable, which is coupled to the lever member, a memory gear, which is mounted on a seat back frame, and a sector gear, which is coaxial with the lock mechanism. When the memory operation lever is operated and the first cable is pulled, the lever member is rotated and the second cable is pulled, thereby causing the memory gear to mesh with the sector gear. The sector gear is detachably held with respect to the seat cushion frame by friction of a plate spring secured to the seat cushion frame. The plate spring restricts rotation of the sector gear from an initial position in one direction (corresponding to the direction in which the seat back frame is inclined rearward).
When the lock mechanism is unlocked after the memory gear meshes with the sector gear, the memory gear and the sector gear rotate integrally. A predetermined delay clearance is provided between an engagement pin that is in an initial state and an interlock lever such that the memory gear and the sector gear mesh with each other before unlocking the lock mechanism.
When the sector gear is rotated, the pin that is engaged with the sector gear is disengaged, and a holding link on which the pin is integrally formed keeps the mesh between the memory gear and the sector gear, and the unlocked state of the lock mechanism.
When the seat back frame is inclined rearward and returned to the original position, the sector gear returns to the initial position with the memory gear, and the memory gear and the sector gear move out of the mesh. The seat back is then restored to the angular position at which the seat back was held immediately before being inclined forward.
[Prior Art Documents]
Patent Document
Patent Document 1: Japanese Laid-Open Patent Publication No. 2006-271581